I'm a convert. I've been to Disney 3 times. As a kid, I went to the Magic Kingdom (it was at the time the only park) and I enjoyed it. In high school, I went to Epcot (it was either that or MK) and I enjoyed it. But I didn't have a real burning desire to revisit either one.
A couple of years ago, I married a real Mickey Mouse nut. She'd never been to WDW, so I figured it would be a real treat for her to go on our honeymoon. I was looking forward to it, but I also thought I was making a bit of a sacrifice because I wasn't a Disney fan and I'd already been twice.
Well, my wife enjoyed herself. But she's not a real theme park fan and she got kind of burned out on it by the time we left. I, on the other hand, had the time of my life and can't wait to go back. Go figure.
Much like the original poster, I kind of kick myself now. I didn't truly appreciate WDW until I got back and started reflecting on it and visiting sites like this. If I had my last trip to do over again, there are so many things I'd do differently.
But now, we have a new born daughter. And in a few years, we'll take her to WDW for the first time. And I know I'll appreciate every momment of that!